Last year, high school senior Gaby Rodriguez tucked a faux baby bump under her shirt and went to class. She attracted stares and the usual mean-spirited gossipy comments, all of which she jotted down. She then took her notes and parlayed them into a book, The Pregnancy Project, and a Lifetime movie of the same name that premieres on Jan. 28.

What’s so epic about teen pregnancy that it warrants the one-two punch of a book-and-movie deal? Well, Rodriguez, from Toppenish, Wash., wasn’t really pregnant. It was all — surprise! — part of an academic exercise to examine stereotypes about teen pregnancy.

Rodriguez’s charade angered some, who felt she was being disingenuous by lying to friends and family about her situation (her mother, boyfriend and principal knew about the deception). Others lauded her for calling attention to the U.S. teen pregnancy rate, which is the highest in the developed world.

In her book, Rodriguez shares for the first time why she did what she did, and the explanation is a doozy: her mother Juana got pregnant at 14. Fourteen-year-olds are in eighth grade, for the most part. That’s not even high school age. Long before she could secure a learner’s permit, Rodriguez’s mother was preparing to raise a child.

“I wanted to do something that would impact my school and my community, and decided to start with something small, to bring an awareness of teen pregnancy,” Rodriguez told Publisher’s Weekly. “At a time in their lives when teens are becoming sexually active, they need to realize how the decisions they make now will ultimately affect their lives. And those teens who do become pregnant need to know that it’s not the end of the road. They can find support for themselves and their child, and can move forward.”

Rodriguez is speaking from experience. Her mother married the 16-year-old father of her first baby and went on to have seven kids. Their three daughters (Rodriguez was born to a different father) all wound up as pregnant teens, and two of their sons got their girlfriends pregnant. All of a sudden, the reason for the book-and-movie deal is becoming clearer — particularly since Hispanic teens like Rodriguez get pregnant more often than other minorities do.

“It’s hard to understand why they didn’t learn from each other; I guess they all needed to make their own mistakes,” Rodriguez wrote in her book. “They have great kids, but it’s never easy to have children before you’re even fully grown yourself.”

Last week, the Centers for Disease Control and Prevention released a survey of nearly 5,000 girls in 19 states who got pregnant unintentionally and gave birth in the period from 2004 to ’08. Half had not used birth control and a third explained their reasoning by saying they didn’t think they could get pregnant. In fact, research has shown that girls who get pregnant in their teens are often woefully misguided about their menstrual cycles. Some thought there was no way to get pregnant at the same time they lost their virginity, while others had an incorrect understanding of how ovulation works and at what point in the month they were most fertile.

Still, more teens than ever seem to be clueing in to how their bodies work. Yes, the U.S. teen pregnancy rate still towers above other countries’, but the teen birthrate has dropped to 34.3 births per 1,000 girls ages 15 to 19, down from a peak of 61.8 in 1991.

According to the Associated Press, Rodriguez was curious about how people would react if she appeared to follow in her family’s footsteps — then defied that expectation:

In the top 5% of her class, Rodriguez participated in a leadership class and lectured her friends about safe sex. But she still heard the refrain — often from members of her own family — that she’d end up just like her sisters.

“Being a Hispanic girl from a family full of teen pregnancies meant that my odds of also becoming a teen mom were way higher than average,” she wrote. “If I gave people what they predicted, how would they react?”